Electrical safety attachment for knitting machines



Oct. 31, 1950 J. s. KARL 2,527,822

ELECTRICAL SAFETY ATTACHMENT FOR KNITTING MACHINES Filed Aug. 4, 1948 .W{ml -'//Y5ULAT/OA/ INSULAT/OIV/ 'L A L IN V ENTOR.

. ATTO/P/VEV Patented Oct. 31, 1950 ,oFFlCE.

KNITTING MACHINES Josef S. Karl, Athens, Ga.

Application August 4, 1948, Serial No. 42,476

Full .fashioned hosiery machines and other machines of a similar typesuch as are fully shown and described in a book entitled The ReadingFull Fashioned Knitting Machines Copyright 1940 by Textile MachineWorks, in-

volve the inter-action of sinkers and dividers with the needles andthread carriers, movements of the sinkers and dividers being controlledat times by the catch bar. In case of displacement of the catch baroffailure of timing of the thread carriers with respect to the sinkersgreat damage and loss of time may result. For instance, thread or otherforeign matter sometimes gets into the slot of the catch bar or a sinkeror divider may be frozen in its slot. In such cases, the catch bar inits positive forward motion will actually jump above the backs of thesinkers and dividers. If the machine continues to run, the threadcarrier would quickly run over the sinkers that were left sticking outand injure or destroy them. Sometimes a carrier friction may become tooloose or a leather fall out or motion will otherwise not be properlytransmitted to the carrier. As the sinkers come forward a short timeafter the carrier passes across, if the carrier slows or stops thesinkers may become damaged by the carrier tubes which extend below theupper edge of the sinkers. If the sinkers become damaged, they may stickand cause the catch bar to jump.

It is the purpose of my present invention to prevent costly smashes onsuch machines. I accordingly provide electric switches which cause asuitable brake to be applied and stop the machine in case the sinkersadvance before the thread carriers are in a safety position. Theoperator cannot start the machine until the fault is remedied.

Fig. 1 is a front view of a section af a machine with a. single threadcarrier and rod and to which I have applied the safety switch of myinvention.

Fig. 2 is a transverse sectional view showing a 2 single carrier rod andcarrier.

Fig. 3 is an enlarged fragmentary sectional view showing the support fora thread carrier and its contact rod.

I have shown conventional carrier rod brackets 8, 8 which are supportedby. a part 9 of the frame and which support the carrier rods I!) inslots H. Usually there are eight of these rods to each section and eachrod supports a metallic thread carrier assembly having a carrier fingerl2 and its bracket 12, for instance, by means of the screws 13. Eachcarrier has a thread guide tube M at its lower end and the carrierfunctions in 3 Claims. (Cl. 66-465) the usual manner in connection withthe 'usual sinkers l5 and dividers Hi. The carriers are suitablyinsulated from the frame. Each carrier isprovided at its lower end withswitch contact members 11, ll "inthe form ofwires whicli'extend down toor almost down to the level of the lower end of the guide tube [4 of thecarrier to which they are attached. These contact wires should be muchfiner in diameter than the diameter of the thread guide tubes and shouldextend slightly below the level of the upper edges of the sinkers. Thetips of these contact wires may extend laterally of the guide tube asfar as necessary to give a quicker action or contact if the correctmotions of the sinkers and carriers are not in accurate timing with eachother. The other contact of the switch is in the form of a rod 20, theends of which are supported. in insulating pieces 2| which are attachedto the bracket 8, 8 by screws 22, 22. There is one of these contact rods20 for each of the carriers in a given section and they are connected inparallel to one pole of a motor and brake control switching device 23,the sinkers and the grounded frame of the machine being connected to theother pole of the brake control switch. The carrier and its bracket I2are insulated from the carrier rod by layers of insulation 24 and has asliding connection with the contact rod 20. For this purpose I mayprovide a loop 25 surrounding the rod 20 and having its ends passthrough the carrier and riveted over as shown in Fig. 3. To ensurecontact with the rod 20, I may provide a washer 26 which is pressedagainst the rod 29 by spring 21 beneath the thread carrier.

Should the carrier motion get out of time with the sinkers, the sinkerswill advance and catch up until a sinker makes contact with one of thecontact wires I! on either side of the carrier depending on whether ittravels from right to left or left to right. This will close a circuitand actuate relays for shutting off power and applying a brake to stopthe machine. This circuit is provided with a suitable source of lowporanged not only to disconnect the machine driving motor from the powersupply therefor, but also be arranged to actuate a suitable brake, for

example of the solenoid or of the dynamic type,

in order more rapidly to stop the machine,

ing the switches above described will employ a low voltage.

The form of braking mechanism is also immaterial and it may be of thewell known dynamic brake type or solenoid actuated type.

1. As an article of manufacture, a'thread carrier having a guide tubeand a contact wire on each side of the tube, the contact wires being ofless diameter than the guide tube and extending down to the approximatelevel of the lower end of the guide tube.

2. Safety means for a hosiery knitting machine comprising in combinationwith carrier brackets and a carrier rod, a carrier and sinkers, a.contact rod carried by but insulated from the brackets and contact wirescarried by the carrier and extending laterally thereof to engage withsinkers in case the carrier and sinkers get out of proper timedrelation.

3. In a safety switch for a knitting machine the combination of twospaced carrier brackets with i r carrier rods, 2, thread carriersupported by each rod but insulated therefrom, a contact rod carried bysaid brackets but insulated therefrom adjacent each carrier, a contactcarried by each carrier and slidable against the contact rod adjacentthe carrier rod on which said carrier is mounted and a contact wirecarried by said carrier alongside of its guide tube.

- J OSEF S. KARL.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

